"And yes, I don't know how to speak French."
Let's break it down:
* et oui: This is a common expression in French, meaning "and yes" or "indeed."
* je ne sais: This is a standard way of saying "I don't know" in French.
* comment parler français: This translates to "how to speak French."
So, the whole sentence expresses someone acknowledging that they cannot speak French.